Your issue with Hyperbowl crashing is related to you nVidia drivers. Plus hyperbowl and the fish screen saver seem to be the best program to run to duplicate the crash that happens with nVidia cards/drivers and XP. The is still no real solutin available just some changes that can be made to lessen the problem.

What worked best for me was to turn off sideband addressing and fastwrites also set AGP appature to 64 or less.

I also heard that using any theme other than the default XP theme style seemes to help.